E117

30.9.2009
Patent E117 - IP Portfolio A1

Regenerative Accumulator-Buffered Electro-Hydraulic Brake Booster

Inventors: H. Leiber, Dr. T. Leiber, V. Unterfrauner, C. Köglsperger

2 Core Innovations

Patent E117DE

MultiStore Follow-Up Brake Booster – Brake System with Multifunctional Reservoir for ABS and Blending

Patent Status : Revoked in 1st Instance - Under Appeal

Patent E117DE1

RekuBlend Brake – Pressure Accumulator-Based Blending with Constant Pedal Feel

Patent Status : Revoked in 1st Instance - Under Appeal

Patent E117DE (DE102009043484)
Keyword: MultiStore Follow-Up Brake Booster – Brake System with Multifunctional Reservoir for ABS and Blending

  1. Brake system for a hybrid vehicle with a control device and a brake pedal (1) which acts mechanically on a piston (3) of a piston-cylinder system to generate brake pressure, 
  2. wherein an electric drive additionally acts on the piston (3) of the piston-cylinder system to support the force of the person actuating the brake pedal (1), and the pressure build-up in wheel brakes (RB) takes place by adjusting the piston (3), and each wheel brake (RB) or each brake circuit is assigned at least one switching valve (7) which is used to maintain pressure in the assigned wheel brake(s). the associated wheel brake(s) (RB) and is opened to change the pressure in the associated wheel brake(s) (RB), 
  3. wherein the control device controls the drive (2) as a function of the master cylinder pressure or wheel brake pressure predetermined by the person or by a brake controller in order to control a piston position and a drive force, 
  4. wherein a fluid reservoir (20, 20') is assigned to at least one wheel brake (RB) or at least one brake circuit, the reservoir chamber of which can be selectively connected to a pressure line (BL) of the wheel brake (RB) or the brake circuit via a switchable reservoir valve (8), 
  5. wherein in the ABS function the fluid reservoir (20, 20') serves selectively to receive fluid from this wheel brake or the associated brake circuit when the pressure in a wheel brake (RB) is reduced, characterized in that 
  6. the brake pedal (1) acts mechanically via an elastic member (15) on the piston (3) of the piston-cylinder system to generate brake pressure, and 
  7. wherein a force reaction on the brake pedal (1) is set when a generator braking torque of an electric drive of the hybrid vehicle is applied by adjusting the piston (3) by means of the drive while simultaneously filling the fluid reservoir (20, 20').

Claim Features

Abstract:

The invention relates to an electro-hydraulic brake booster in which the brake pedal acts mechanically via an elastic element on a piston which provides power-assisted brake pressure by means of an electric drive, whereby a controlled force reaction is generated on the pedal during recuperative generator braking by targeted piston movement and filling of a fluid reservoir, while switchable valves regulate pressure build-up, reduction and maintenance in the wheel brakes.

Technical Relevance:


The technical relevance of the invention lies in the possibility of generating high regenerative vehicle deceleration and realistic, adaptive, pleasant pedal feedback during regenerative braking in hybrid vehicles through targeted piston adjustment and the use of a fluid reservoir, thereby efficiently combining driving comfort, safety and the integration of recuperation and hydraulic braking.

Patent E117DE-TA1 (DE102009061809)

CLAIM 1
Keyword: RekuBlend Brake - Pressure Accumulator-Based Blending with Constant Pedal Feel

  1. Brake system for a hybrid vehicle with a control device and a brake pedal (1), 
  2. which acts mechanically via an elastic member (15) on a piston (3) of a piston-cylinder system (5) to generate brake pressure, 
  3. wherein an electric drive (2) additionally acts on the piston (3) of the piston-cylinder system (5) to support the pedal force, 
  4. wherein the control device controls the drive (2) as a function of 
    • of the main 
    • and/or wheel brake pressure specified by the person and/or by a brake controller 
    • and/or wheel brake pressure for controlling a piston position and a drive force 
  5. for pressure build-up and/or pressure reduction in at least one wheel brake (RB) or at least one brake circuit (22), 
  6. wherein a fluid reservoir (20, 20') is assigned to at least one brake circuit, the reservoir chamber of which can be connected to the wheel brake (RB) or the brake circuit via a switchable reservoir valve (8), 
  7. wherein a force reaction on the brake pedal (1) takes place when a generator braking torque of an electric drive of the hybrid vehicle acts by adjusting the piston (3) by means of the drive (2) with simultaneous filling of the fluid reservoir (20, 20').

Claim Features

Abstract:

The patent describes an electro-hydraulic fail-safe brake-by-wire braking system, designed for a hybrid vehicle, in which the brake pedal actuates a piston in the master cylinder via a spring element, while an electric motor adjusts the same piston in a force-boosting manner. A control unit mixes driver and controller requirements, regulates piston position / piston drive force and can switch on a hydraulic accumulator for each brake circuit via a valve: During recuperation, the accumulator is filled, the desired wheel or circuit-specific brake pressure is built up/reduced and a natural pedal feel is simulated at the same time.

Technical Relevance:


The system combines an electrically assisted master cylinder with a switchable hydraulic accumulator, which buffers the generator braking torque during recuperation and thus, in the event of high regenerative vehicle deceleration, builds up or reduces wheel or circuit braking pressure at high speed without distorting the pedal feel; the brake booster and ESP unit thus work together synergistically, while the mechanical pedal coupling and software-based control simultaneously meet the fail-safe and flexibility requirements of modern hybrid and electric vehicles.